Sourpouhi Bedikian

A search for a 130 GeV charged Higgs boson in ttbar events containing a tau lepton is presented. Tau polarimetry is used in order to distinguish the signal, t → H±b → τνb, from the dominant Standard Model background, t → W±b → τνb. The signal extraction is performed by a log-likelihood template fit. The dataset corresponds to an integrated luminosity of 4.6 fb^−1 of sqrt(s)=7 TeV proton-proton collisions collected with the ATLAS detector in 2011 at the Large Hadron Collider. Assuming the H± decays exclusively to τν, a limit is placed on the BR(t → H±b) of less than 16% at the 95% confidence level. This is the first search for physics beyond the Standard Model to use τ polarimetry at a hadron collider.